Combination fuel pump and fuel injector for diesel engines



Mfay 31, 1932.- Y l|L| LE PU1 1,860,865

COMBINATION FUELJ PUMP AND FUEL INJEcToR FoRDIEsEL-ENGINES l l Y Filed Nov. 18, 1929` v 52; vii 11,2@

35- INVENTOR f w .B-Y-HE/VRY 1.57704..

Patented May 31, 1932 UNITED STATES PATENT OFFICE HENRY LE PUL, F HEMPSTEAD, NEW YORK COMBINATION FUEL'IPUMP AND FUEL INJECTOR FOB DIESEL ENGINES Application filed November 18, 1929. Serial No. 407,802.

inlet passage connecting with a fuel com-- pression chamber, said plunger arranged upon' its init-ating stroke topass said inlet passage and entrap and compress the fuel.

Within the chamber, and a blow-off valve connected'with said fuel chamber for directing the discharge of the fuel under pressure into a cylinder of said engine. The invention further proposes the provision of separate body sections constituting the said body and one of said body sections being provided with said inlet passage and adjustable in position for determining the size of the fuel compression chamber for feeding regulated quantities of fuel to the engine for throttle control. j

As is well known, it is necessary to inject solid fuel at high pressures into Diesel engines. The customary arrangement, for doing this is the provision of the fuel pump external to and not a part of the engine for supplying fuel under 4the desired pressures, and the provision of an injector on each cylinder for controlling the injection of the fuel under pressure into the engine. The present invention is calculated to simultaneousiy raise the fuel to the proper pressure and `to inject it into the engine. This arrangement permits common parts for raising the pressure and for injecting and thus prodeces a saving ail around in addition togain ing efficiency due to a reduction of Working parts. Y

For further comprehension ofthe invention, and of the objects and advantages thereof, reference will ne had to the following description and accompanying drawings, and

to the appended claims in which the various novel features of the invention are more particularly set forth. t

In the accompanying drawings forming a material part of this disclosure Fig. 1 is a vertical sectional'view of a combination pump and injector constructed a'ccording to this invention, certain parts beingshown in elevation.

Fig. 2 is a horizontal sectional view taken o0 on the line 2 2 of Fig. l.

Fig. 3 is a horizontal sectional view taken on the line 3-3 of Fig. 1, and

Fig. 4 -is an enlarged detailed view of aportion of Fig. 1 showing all parts in section. 65 The combination'fuel pump and fuel in' jector for Diesel engines consists of a plunger 10 for operation by the cam shaft of an engine and working in a body member 11 formed with an inlet passage 12 connectin 70 with a fuel compression chamber. 13, sai plunger 10 being arranged upon its injecting' stroke to pass said inlet passage 12 and entrap and compress the fuel'within the chamber 13, and a blow-olf valve 14 connected with I5 fuel chamber -13 for directing the discharge of fuel under pressure into a cylinder of the said engine. The body 11 is made from several sections, only one of said sections being V provided with the said inlet passage 12. This section is adjustable in position for determining ther-size of the fuel compression chamber 13 for feeding regulated quantities of fuel to the engine for lthrottle control.

The said body member 11 consists of an 85 inner section 15, an intermediate section 16 and an outer section 17. The inner section 15 has a central borev 18 extending its complete length, and also has avbottom reduced 'j portion 19, a central flange portion 20 and a 90 top externally threaded portion 21.

The said intermediate section 16 has a central bore 22 extendin its full len h and is slidably mounted on t e bottom re uced portion 19 of the inner section 15. The inter- 95.

to a small distance from the bottom end, and

is adapted for attachment upon the cylinder of an engine. The outer section terminates at the top in a pair of lugs 27 which are engaged against the bottom side of the said central flange 20. Screws 28 engage thru the flange `and into the lugs for holding the outer section in fixed relation to the inner section.

l lateral passage 29 in the outer section 17 aligns with the passage 12 in the central section. A pair of lugs 30 project from one side of the outer section 17 and support a, pin 31 carrying a rocker arm 32 with teeth at one end meshing with the rack teeth 25. A control lever 33 is attached upon the pin 31 so that upon motion of the lever, the rocker arm moves for raising or lowering the interme diate body section 16. A valve seat' 34 is formed in the outer body section 17 at the bottom of the bore 26 and connects with a passage 35 for discharging into a cylinder of the engine. f

The said plunger 10 has a finished central portion 36 and an enlarged bottom head 37. The central portion 36 is slidably engaged thru the bore of the inner section 15 and is formed with a plurality of packing grooves 38 adapted to be filled with oil for forming an oil packing. A packing gland 39 threadedly engages in the inner section and forces packing material 40 tightly between the inner section and the central portion of the plunger rod for forming a liquid tight joint.

The enlarged head portion 37 of the plun er is disposed within the intermediate bo y section 16 and is a slidable fit in its central bore. The top of the enlarged head portion 37 is slightly spaced from the bottom end of the inner body section 15 providing a space which constitutes the fuel chamber 13. A transverse fuel aperture 45 is formed within the plunger 10 and communicates with the' fuel'chamber 13. A longitudinal fuel passage 46 connects with the transverse passage 45 and communicates with a bottom bore 47 formed in the bottom end of the plunger 10. This bore is so arranged to provide a valve seat 48.

A bottom plug 49 threadedly engages on the bottom end of the enlarged head 37 of tbe plunger and is formed with a bottom pro- 'ection 50 constituting a valve head for act# ing against the said valve seat 34 in the outer body section 17. Fuel passage grooves 51 extend from the valve head 50 to a bore 52 within the bottom plug 49 and which aligns with the bore 47 in the plunger. A valve head 53 is slidably engaged within the bores movement of the valve. As shown 1n Fig. 4 'the valve is of hollow construction so as to house the expansion spring 54.V A spiral fuel A passage groove 57 is formed upon'the periphery of the valve 53 so as to permit the passage of fuel from the longitudinal passage 46 to the passages 51 and hence, if the valve 50 is open, to the passage 35.v

A spring housing 58 is threadedly engaged upon the threaded portion 21 of the inner body section. A collar 59 is fixed upon the plunger 10 and an expansionl spring 60 .acts between the collar and the spring housing 58 for normally urging the plunger down wards. Lugs 61 project from the spring housing 58 and support a pin 62 carrying a rocker arm 63 engaging the bottom side of the collar 59. A lever 64 is fixed upon the pin 62 and is intended for connection with the cam shaft of the engine.

In operation of the device, a supply of fuel is fed into the passage 29. This fuel enters the fuel chamber 13 thru the passage 12. At the proper moment as determined by the cam shaft of the engine, the lever 64 is `moved so that the rocker arm 63 lifts the plunger 10. As the plunger moves upwards, the head portion 37 forces back all excess fuel from the fuel chamber 13 until it passes the passage 12 and then compresses the entrapped fuel within the chamber 13. Continued upward motion of the plunger soon raises the pressure of the entrapped fuel to a" i predetermined l amount as determined bythe strength of the spring 54.

As this pressure is reached, the Valve 53 automatically moves downwards and the fuel.

easy to raise a pressure of the inlet fuel to 5,000 lpounds or more with this arrangement.

As the plunger 10 moves upwarf'; a chamber will be formed under the bottom plug 49 of the plunger head 37. This chamber will increase at a greater rate than the decrease of the annularfuel chamber 13. As this chamber is formed, hot air from within the cylinder of the engine will pass through the passage to fill the same. Simultaneous with this passage, fuel which is pressed out from the annular chamber 13 will be discharged at a great velocity against the-conical sides of,

the seat 34 and there be deiected through the passage 35. The yalve 53 opens when the fuel oil is under a pressure of 5,000 lbs. which,

due to the velocity, can easily take the right of wa through thepassage 35 against incoming air which at most is only at a pressure of 500 lbs. This incoming air 4will cause burning of the fuel within the newly formed com-4 posit ion,all of the vapors and all of the liq-j nid fuel within the newly formed chamber will be discharged into the cylinder of the engine. It is pointed out that the volume of air in the newly formed chamber is small and can support but a very small percentage of the combustible property of the fuel oil discharged on each stroke (for example, from 1% to 5%) so that a large percentage of combustion takes place in the cylinder of the Diesel engine.

The quantity of fuel injected into the engine at each operation of the device may be controlled by manipulation of the lever 33. Motion of the lever moves the rocker arm 32 and consequently raises or lowers the intermediate body 4section 16. As the body section is raised, the position of the fuel passage 12 is changed relative to the bottom end of the inner body section 15. Consequently the size of the portion of the fuel chamber which holds the entrapped fuel is varied.

. While I have illustrated and described my invention with some degree of particularity, I realize that in practice various alterations therein may be made. I therefore reserve the right and privilege of changin the .form of the details of construction or ot erwise altering the arrangement of the` correlated'parts without departing from the spirit or the scope of the appended claims.

Having thus described my invention, what I claim as new,and desire to secure by United States Letters Patent is 1. In a combination fuel'pump and fuel injector for Diesel engines, a body member comprising an inner section with a reduced lower end and a central bore, an intermediate section slidably mounted on said reduced end and extending below sa-idreduced end and formed with a fuel inlet passage terminating slightly below the reduced end and in a fuel compression chamber, and an outer section encasing said intermediate section and xedly connected with the inner section and formed with a fuel'passage'aligning with said inlet passage, a plunger slidably mounted in the bore of the inner body section and formed with an enlarged head slidably mounted within'the portion of the intermediate body section-below the inner body section and normally slightly spaced from the lower end of the inner body section for 4forming said fuel compression chamber, a valve head ou the plunger and engaging with its end against a valve seat on the outer body section communicating with a passage constituting a fuel outlet, a blow-off valve in said plunger interposed in a passage between said fuel compres- 'sion chamber and the end of said valve head,

andmeans for adjusting the position'of the intermediate body section for adjustments of the sizeof a portioniof said fuel compression chamber in which. fuel is entrapped upon motion of said plunger to move its valve head from said valve seat.

2. Ina combination fuel pump and fuel injector for Diesel engines, a body member comprising an inner section with a reduced lower end and a central bore, an intermediate section slidably mounted on saidreduced end and extending below said reducedA end and lformed with a fuel inlet passage terminating slightly below the reduced end and in a fuel compression chamber, andan outer section encasing said intermediate section and ixedly connected with the inner section and formed with a fuel passage aligning with said inlet passage, a plunger slidably mounted in the bore of the inner body section and formed with an enlarged head slidably mounted within the portion of the intermediate body section below the inner body section and normally slightly spaced from the lower end of the inner body section for forming said fuel compression chamber, a valve head on the plunger and engaging with its end against a valve seat on the outer body section com.- municating with a passage constituting a fuel outlet, a blow-0E valve in said plunger interfrom said valve seat, comprising lateral rackv teeth on said intermediate body section, a rock arm with teeth meshing with' said rack .posed in a passage between said fuel compresy teeth and pivotally supported on said outer body section, and means for movingthe rocker arm. l 3. In a combination fuel pump and fuel injector for Diesel engines, a body member comprising an inner section with a reduced lower end and a central bore, an intermediate' section engaged on said reduced end and eX- tending below said reduced end and formed with a fuel inlet passageterminating slightly below the reduced end and in a fuel compresv sion chamber and having lateral teeth at the top, and an outer section encasing said inter- `l mediate section and fixedly connected with the inner section and formed with a fuel passage aligning with said inlet passage, a plunger slidably mounted in the bore of the inner body section and formed with an enlarged head slidabl mounted within the portion of the interme iate body section below the inner body section and normally slightly spaced from the lower end of the inner body section for forming said fuel compression chamber, a valve head on the plunger and engaging with its end against a valve seat on the' outer. body section communicating with a passage constituting a fuel outlet, a blow-olf valve 1n said -plunger interposed in a passage between said fuel compression chamber and the end of said valve head, aflug supported on one side of said outer section, a rocker arm piv-y otally mounted upon said lug and having teeth meshing with said teeth on the inter- K mediate section, and a control lever connected with said rocker arm to move the intermediate section when desired.

Signed at New York, in the county of New York and State of New York, this 9th day of November, A. D. 1929.

HENRY LE PUL. 

